Daily NEET MCQ- April 16, 2022 - NEET MCQ

The stopping potential is directly proportional to the frequency of light. Hence, the stopping potential increases with an increase in the frequency of the incident light.

No effect. This is because the intensity of radiation incident on a photo-sensitive plate is independent on stopping potential. So, the stopping potential remains the same, even if the intensity is doubled.

Isomorphous is when two or more substances have the same crystal structure. Polymorphous is when a single substance can crystallize in two or more forms depending upon the conditions.

Quartz glass does not have a perfectly ordered structure, hence it is classified as an amorphous solid. The rest are crystalline solids due to ordered structures.

Crystalline solids have a perfectly ordered structure which collapses immediately at a specific temperature. Amorphous solids melt over a range of temperatures, not one specific value.

The presence of protease (protein digesting enzymes) and RNase (RNA digesting enzymes) in the presence of the virulent or avirulent strains will not affect the process of transformation. But on the contrary, when the DNase is present, the process of transformation will not occur. This proves that the transformation process cannot occur as long as the DNase enzyme is present. The role of nuclease is to cleave the phosphodiester bonds between the nucleotides of nucleic acids.

Only DNase has the ability to inhibit transformation. The other enzymes like RNase and lipase do not possess that ability. The process of transformation is not seen when the biochemical DNase is with S-strain. Lipase is an enzyme that catalyzes the hydrolysis (H2O addition) of lipids and fats. The process of transformation will occur in lipids. As a result, R-strains will be produced in lipids.

The mouse fed with the S-strain from the Staphylococcus pneumoniae, happens to naturally die. This is on an account that the S-strains are virulent. Under such conditions, the mouse will not be able to survive. But, when the heat killed S-strains from Staphylococcus pneumoniae are injected into the mouse, it will live.

Prior to the works done by Oswald Avery, Colin MacLeod and Maclyn McCarty, the genetic material was thought to be as the protein. Nucleoids are the irregular shaped structures in the prokaryotic cell. They contain nearly all of the genetic material of the prokaryotes. Nucleons are present inside the nucleus of an atom, alongside with the protons. Chromosome carries the genetic information of the genes.

Joseph Priestley discovered O₂ in 1774. He found the presence of oxygen during his experiment. In a jar containing a mouse, a candle and a mint plant, he found out that the mouse was alive and the candle was lit up. This showed that the mint plant gave oxygen to the enclosed jar.